Subsurface safety valve with auxiliary control fluid passage openable in response to an increase in control fluid pressure

ABSTRACT

A valve for installation in a flow conductor for controlling flow of fluids through the conductor, which may be controlled from a remote point and which may act automatically as a safety valve, including means for positively propping the valve in an open position or in a position intermediate open and closed positions for taking the valve out of operation permanently or for flowing the well without affecting operation of the valve, and further including means for locating and operating a supplemental flow control valve at such point in the flow conductor. Also includes means normally closing a lateral control fluid passage in the housing of the valve which is openable by increased control fluid pressure for thereafter conducting control fluid to and controlling a supplemental flow control which may be disposed through the valve.

United States Patent Calhoun [4 1 May 13, 1975 INCREASE IN CONTROL FLUID PRESSURE 3,799,258 3/1974 Tausch 166/224 A Primary Examiner-James A. Leppink Attorney, Agent, or Firm-Albert W. Carroll [57] ABSTRACT A valve for installation in a flow conductor for controlling flow of fluids through the conductor, which may be controlled from a remote point and which may act automatically as a safety valve, including means for positively propping the valve in an open position or in a position intermediate open and closed positions for taking the valve out of operation permanently or for flowing the well without affecting operation of the valve, and further including means for locating and operating a supplemental flow control valve at such point in the flow conductor. Also includes means normally closing a lateral control fluid passage in the housing of the valve which is openable by increased control fluid pressure for thereafter conducting control fluid to and controlling a supplemental flow control which may be disposed through the valve.

15 Claims, 19 Drawing Figures PATENTED MAY 1 31975 SHEET 1 U? S FIG. i-A

FATENTED HAY l 3 i975 SHEET PATENTED 3.882.935

saw u or 5 11 16.12. FIG. 15 PIG-1A- PEJENTEUW I 101's 7 3.882.935

SUBSURFACE SAFETY VALVE WITH AUXILIARY CONTROL FLUID PASSAGE OPENABLE IN RESPONSE TO AN INCREASE IN CONTROL FLUID PRESSURE This invention relates to well flow control valves and more particularly to subsurface automatic safety devices for controlling the flow of fluids through flow conductors in wells and which may be responsive to the flowing well fluids for operation or may be surface controlled.

The invention illustrated and described hereinbelow is an improvement over the well control valves illustrated and described in US. Pat. No. 3,696,868 issued to Donald F. Taylor, Jr. on Oct. 10, 1972. It is also an improvement over the subsurface safety shut-off valve apparatus illustrated and described in US. Pat. No. 2,998,077 issued to Julian D. Keithahn on Aug. 29, 1961.

It is one object of this invention to provide a subsurface safety valve having means for holding the valve in open position or in a position intermediate open and closed positions.

It is a particular object of this invention toprovide a well flow control valve including means for installing a supplementary valve therein after the original valve has first been locked in an inoperative position.

Another object of this invention is to provide in a valve of the character just described means for operating the valve by control fluid pressure conducted thereto from the surface.

A further object of this invention is to provide a valve of the character just described having lateral control fluid passage means leading into the interior of the valve so that a supplemental valve disposed in the first valve may be controlled also by the same control fluid pressure.

Another object of this invention is to provide means in said control fluid passage normally blocking admission of control fluid into the interior of the valve but which is openable after the original valve has been locked in an open or in an intermediate position.

Other objects and advantages will become apparent from reading the description which follows and from studying the accompanying drawing wherein:

FIGS. l-A, l-B, l-C, and 1-D together form a longitudinal view, partly in section and partly in elevation with some parts broken away, showing a flow control valve embodying this invention in open position;

FIG. 2 is a cross-sectional view taken along line 22 of FIG. 1;

FIG. 3 is a cross-sectional view taken along line 33 of FIG. 1;

FIG. 4 is a cross-sectional view taken along line 44 of FIG. 1;

FIG. 5 is an enlarged fragmentary view showing means for releasably plugging the lateral control fluid flow passage in the device of FIG. 1;

FIG. 6 is a fragmentary longitudinal view, partly in section and partly in elevation with some parts broken away, showing the device of FIG. 1 with the valve mechanism in closed position;

FIG. 7 is a fragmentary view similar to FIG. 6 showing the lock sleeve shifted to position holding the valve open;

FIG. 8 is an enlarged fragmentary view similar to FIG. 5 showing the plug means of the device of FIG. 1

being expended to open the lateral control fluid passage;

FIGS. 9-A and 9-8 together form a view similar to FIG. 6 showing the latch sleeve in position holding the valve open, showing the lateral control fluid passage open, and a supplementary flow control valve disposed in the original device of FIG. 1 for controlling well flow therethrough;

FIG. 10 is an enlarged fragmentary view similar to FIG. 5 but showing disk means for closing the lateral control fluid passage;

FIG. 11 is an enlarged view similar to FIG. 10 but showing the disk means in ruptured condition opening the control fluid passage;

FIG. 12 is a longitudinal view, partly in section and partly in elevation with some parts broken away, showing the upper portion only of a modified form of device having a rupture disk closing the lateral control fluid passage therein, control fluid pressure normally existing on both sides of the disk;

FIG. 13 is a fragmentary view similar to FIG. 12 showing the device of FIG. 12 with the lock sleeve in position holding the valve open and the lateral control fluid passage open, the disk therein having been ruptured; i

FIG. 14 is a view similar to FIG. 12'but showing a further modified form of the invention having rupturable disk means closing the lateral control fluid passage therein, the disk being carried in the shiftable latch sleeve, well pressure normally existing on both sides of the disk; and

FIG. 15 is a view similar to FIG. 13 showing the device of FIG. 14 with the lock sleeve in position holding the valve open and the lateral control fluid passage open, the rupture disk therein having been ruptured.

Referring now to FIGS. 1 through 8 of the drawing,

it will be seen that the device of this invention is indi cated generally by the numeral 20. It includes a housing 25 which is externally threaded at its lower end at 21 for attachmentto the lower portion T-l of a string of tubing T and internally threaded at its upper end as at 22 for attachment to the lower threaded end of a landing nipple 23 which is internally threaded as at 24 for attachment to the upper portion T-2 of the string of tubing T. Thus, the device 20 is connectable in a well flow conductorto become a part thereof.

Near its upper end, the housing 25 is provided with a longitudinal eccentric flow passage 26 which is threaded at its upper'end as at 27 for attachment of the lower end of a control fluid conductor 28 extending downwardly from the surface control unit 29 which is located on the surface and furnishes pressurized control fluid for transmission through the control fluid conductor to the, valve 20 to hold the same open to permit well products to flow upwardly therethrough from the producing formation (not shown) to the surface where such products are gathered and stored or disposed of all in the usual manner.

The surface control unit 29 includes pilot means (not shown) which will automatically relieve pressure from the control fluid conduit 28 in response to high or low pressure conditions at the wellhead or in the flow line, or in response to abnormal conditions relating to fire, storm, high fluid levels in storage vessels, or the like, depending on the pilots used and how they are installed, and will permit the valve 20 to close to block flow therethrough.

The device comprises a flap valve member which is swingable about pin 31 between an open position shown in FIG. l-D and a normally closed position shown in FIG. 6. The flap valve member 30 is held open by tubular operator member 32 mounted in the housing for longitudinal movement therein between a valve open position, shown in FIGS. l-A, l-B, l-C and l-D, and a valve closed position, shown in FIG. 6. The reciprocable operator member is provided with an external annular piston 32a which is acted upon from above by the pressure of the control fluid in the annular piston chamber 33 to hold the operator member down against the upward bias spring 34 and thus hold the flap valve member in its open position against the bias of spring 31a.

When control fluid pressure is, for any reason, relieved from the control fluid conductor 28 and, therefore, chamber 33, the spring 34 moves the operator member upwardly to its upper position and out of the way of the flap valve member, whereupon spring 310 will swing it to its closed position, shown in FIG. 6, wherein it engages the seat surface 35 and stops all flow through the valve.

It is well known that operator means such as the reciprocable tubular operator member 32 is also well suited for operating valves other than the flap type valve illustrated. For instance, such longitudinally slidably operator means have been used to operate balltype valve closures as is illustrated and described in aforementioned U.S. Pat. No. 3,696,868. They have also been used to operate poppet-type valve closures as is illustrated and described in US. Pat. No. 3,273,588 issued Sept. 20, 1966, to W. W. Dollison. In fact Dollison uses his reciprocable operator means to operate all three such types of valves. It will be noted that each of the three types of valves is open when the operator member is down and closed when the operator is up. Therefore, either type of valve would be usable in the present invention, the flap type valve being illustrated and described herein by way of explanation only.

It may be desirable under some conditions to positively hold the valve 30 of the device 20 open to permit tools or devices to be lowered therethrough or to render the valve inoperative while permitting continued production from the well. In such case, a shifting tool, such as the shifting tool illustrated and described in US. Pat. No. 3,051,243, issued Aug. 28, 1962, to George G. Grimmer, is utilized to engage and shift the slidable lock sleeve to its lower position and lock it there to hold the operator member down and thereby hold the valve open.

If the device 20 has malfunctioned, it may be desirable to install a packoff through it, after the sleeve 40 has first been shifted to its lower position, to hold the valve inoperative and permit continued production of the well. Such a packoff is installed in the manner taught by Taylor in his US. Pat. No. 3,696,868 mentioned above. This packoff tool is supported on a suitable locking mechanism disposed in the landing nipple 23 forming an upper portion of the device 20 and seals carried by the packoff seal between the packoff and the device 20 in the prepared bores 42 and 43 provided in the device near its upper and lower ends, respectively, as shown in FIGS. 9-A and 9-B.

A supplementary or auxiliary flow control valve can be provided in the packoff and its actuation can be controlled from the surface by control fluid conducted thereto from the surface controller 29 through the control fluid conductor 28 in the same manner that actuation of valve 20 is controlled. If such valve is to be installed, then the sleeve 40 must be first shifted to its lower, valve open, position, and the pressure output of the surface controller 29 must be increased until the lateral control fluid passage in the wall of the valve 20 is opened by the failure of rupturable or shearable plug means which has to this time kept such passage closed. In this manner, production of the well may be continued in the usual manner and the supplementary will close any time an undesired condition develops which will cause the surface controller 29 to respond by relieving the pressure from the control fluid conductor 28.

The housing 25 of the device 20 includes a tubular spring housing which is internally threaded at its upper end as at 51 to receive the lower threaded end 52a of the connector 52. An o-ring 53 disposed in a suitable external annular recess near the lower end of the connector 52 seals between the connector and the sleeve 50. The upper end of the connector is externally threaded as at 54'for attachment to the lower internally threaded end of the upper housing 55 and this connection is sealed by an o-ring 56 disposed in a suitable external annular recess formed near the upper end of the connector. The upper end of the upper housing 55 is internally threaded as at 22 for attachment to the lower threaded end of the landing nipple 23 and this connection is sealed by an o-ring 58 disposed in a suitable external annular recess formed on the extreme lower end of the landing nipple. The upper end of the landing nipple is internally threaded as at 24 for attachment to the lower threaded end of the tubing section T-2 of the tubing string T.

The landing nipple 23 is provided with landing recesses 61 formed in the internal wall thereof to provide means for locating and locking a suitable locking device which may be used to support a supplementary valve, or the like, in the device 20, should the device 20 become inoperative. One suitable locking device is that illustrated and described in US. Pat. No. 3,208,531, issued Sept. 28, 1965, to Jack W. Tamplen. Below the recesses 61, the bore 42 of the landing nipple is provided with a smooth finish adapted to receive seal means carried by the locking device or by the supplementary valve, or the like, mentioned above.

The upper housing 55 is provided with a small diameter longitudinal offset or eccentric passage 26 formed near its outer edge and the upper end of this passage is internally threaded as at 27 to receive the lower threaded end of the control fluid conduit 28. The lower end of the passage 26 opens into and communicates with the enlarged bore 64 of the upper housing 55. The passage 26, therefore, communicates the interior of the upper housing 55 with the surface controller 29 through the control fluid conduit 28 for a purpose to be described.

An internal flange 65 is provided in the upper housing 55 and its upper surface 65a provides a stop shoulder which is engaged by the lower end "of the landing nipple 23. The lower surface 65b of the flange 65 provides a stop shoulder which is engaged by the upper end of a tubular sleeve housing disposed inside the upper housing and whose reduced upper end portion 70a is telescoped into the intermediate bore 71 of the upper housing. An o-ring 7 2 is disposed in a suitable external annular recess near the upper end of the sleeve housing 70 and seals between the'sleeve housing and the upper housing 55 as shown in FIG. l-A. The seal 72, therefore, seals the upper end of the annular passage or annular chamber 75 formed between the sleeve housing and the upper housing. The lower end of the annular passage 75 is sealed by the o-ring 56 previously mentioned. The lower end of the sleeve housing is reduced in external diameter as at 70b and is telescoped into the enlarged bore 76a in the upper end of the spacer sleeve 76 and a seal ring 77 disposed in a suitable external annular recess on the lower end of the sleeve housing seals between the sleeve housing and the spacer sleeve.

The lower end of the spacer sleeve 76 is supported on the supper end 52c of the connector 52 and its lower reduced bore 78 is telescoped over the upper end of the valve operator 32 while an o-ring 79 disposed in a suitable internal annular recess in the wall of the reduced bore 78 of the spacer sleeve seals between the spacer sleeve and the exterior of the operator 32. The lower end of the spacer sleeve 76 is grooved or slotted across its lower end as at 80 to provide a pair of radially disposed passages which conduct control fluid from the annular space 75 exterior of the spacer sleeve into the annular piston chamber 33 formed between the connector and the operator 32. In this manner, control fluid is conducted from the surface controller 29 through the control fluid conduit 28 and through the eccentric passage 26 of the housing into the annular space 75 between the upper housing 55 and the sleeve housing 70 and from thence through the cross slot 80 at the lower end of the spacer sleeve into the upper end of the piston chamber 33 where it acts downwardly on the piston 32a. The piston 32a carries an o-ring 81 disposed in a suitable external annular recess formed in the piston, as shown, and seals between the piston and the inner wall 52b of the connector.

When the controller supplies control fluid at normal pressure to the upper side of the piston, the force created against the piston will overcome the upward bias of the spring 34 and will move the operator 32 downwardly to the position shown in FIGS. l-A, l-B, LC, and 1-D, in which position the valve 30 will be held open to permit fluid flow to take place through the device 20.

' The lower reduced end portion 70b of the sleeve housing 70 which is telescoped into the upper end of the spacer sleeve 76 is very short and the enlarged bore 76a in which it is disposed is sufficiently long to provide a recess 76b between the lower end of the sleeve housing 70 and the upwardly facing shoulder 760 of the spacer sleeve. This recess 76b has disposed therein a retainer ring 82 supported on the shoulder 76c and a snap ring 88 supported on the retainer ring. The retainer ring 82 is provided with one or more suitable apertures through the wall thereof for receiving one or more suitable shear pins, such as the shear pin 82a, whose inner ends are disposed in a suitable external annular recess formed in the lower end of a shiftable lock sleeve 40 disposed within the sleeve housing 70. The lock sleeve 40 has an internal bore 83 which is approximately the same size as the bores through the landing nipple and the operator assembly and, in the wall of the bore 83, a plurality of recesses 85 are formed which are engageable by a suitable shifting device such as the shifting tool ST by which the sleeve is shifted downwardly to its lower position wherein it will hold the operator assembly down and, therefore, hold the valve open.

The shear pins 82a releasably retain the slidable lock sleeve 40 in its upper inoperative position where it clears the upper end of the valve operator 32 when it is in its upper position and, therefore, will not interfere with its operation until such time that the shiftable sleeve is moved downwardly by the shifting tool ST to lock the valve open. At this time a downward force applied to the sleeve through the shifting tool ST and suitable wireline tools WLT, or the like, causes the pin or pins 82a to shear and forces the shiftable lock sleeve to be moved downwardly relative to the sleeve housing 70.

A buttress-like thread or longitudinally spaced circumferential buttress-like flanges 86 are formed on the exterior of the slidable lock sleeve 40 and extend from just above the shear pins 82a to a point near'the upper end of the sleeve and these buttress-like flanges are engageable by complementary buttress-like flanges 88 formed in the interior of the ratchet pawl or snap ring 90 disposed in the recess 76b between the retainer ring 82 and the lower end of the sleeve housing 70.

The buttress-like exterior flanges 86 on the sleeve 40 are each formed with a downwardly facing cam shoulder 86a and an upwardly facing abrupt stop shoulder 86b. Similarly, the complementary interior buttresslike flanges 88 in the snap ring are each formed with an upwardly facing cam shoulder 88a and a downwardly facing abrupt stop shoulder 88b. The snap ring is inherently sprung inwardly to the contracted position shown in FIG. l-A and when the lock sleeve 40 is moved downwardly therethrough the cam surfaces 86a onthe lower side of the buttress-like flanges on the sleeve coact with the complementary cam surfaces 88a formed on the upper side of the buttress-like flanges in the snap ring 90 so that the downward movement of the lock sleeve 40 will cam or expand the ring open so that the sleeve can move downwardly through the snap ring.

When the lock sleeve 40 is for any reason thereafter biased upwardly, the snap ring or annular pawl 90 will contract so that the downwardly facing stop shoulders 88b of its inner buttress-like flanges 88 will engage the complementary upwardly facing abrupt stop shoulders 86b of the buttress-like flanges on the lock sleeve 40 to prevent further upward movement of the sleeve relative to the snap ring and sleeve housing. The snap ring, therefore, acts as a ratchet pawl, permitting the sleeve to be moved downwardly relative thereto, and preventing upward movement thereof.

When the lock sleeve 40 is moved downwardly, it is preferably moved to its lowermost position so that the valve 30 will be held fully open. If, however, debris or the like should interfere with the mechanism so that the valve cannot be moved to its fully open position, or the operator assembly 32 or the lock sleeve cannot be moved to their lowermost positions, the lock sleeve 40 will be prevented from moving upwardly so that the operator 32 will be locked in the lowest position reached and the valve will be held open as wide as possible in such case.

At least one lateral passage or aperture and preferably two are provided in the wall of the sleeve housing 70 opposite the upper end portion of the lock sleeve 40 when the lock sleeve is in its upper position as is shown in H6. l-A. Each aperture 100 communicates the interior of the sleeve housing with the exterior thereof so that control fluid from the annular passage 75 will be conducted through the lateral passage or aperture 100 into the interior of the lock sleeve for operation of a supplementary safety valve subsequently placed in the device 20.

The lateral aperture 100 is provided with a large counterbore 101 providing a shoulder 101a, as is shown in FIG. 5, and a plug 102 is disposed in the sperture 100 with its inner end surface 103 in close proximity to the exterior surface of the lock sleeve 40 and may even engage the same. The plug 102 is provided with a suitable external annular recess in which is disposed an o-ring 104 which seals between the plug 102 and the inner wall of the aperture 100. The outer end of the plug is reduced in diameter as at 105 and a flat washer 106 is disposed thereabout while a shear pin 107 is disposed through a suitable aperture near the outer end of the plug with its outer ends extending outwardly from the-plug and being engageable with the washer 106 to retain the plug in place against inward displacement as shown. The washer 106 and the shear pin 107 are disposed within the counterbore 101 of the aperture 100. The plug is sufficiently long so that its outer end is very close to the inner wall 55a of the upper housing 55 to prevent its outward displacement. Therefore, the plug is rather closely confined between the inner wall of the upper housing 55 and the exterior of the upper end portion of the shiftable lock sleeve 40 and cannot move longitudinally out of its sealing position in the aperture 100. The plug will thus prevent the flow of fluids from the annular passage 75 into the interior of the sleeve housing 70 until it is displaced from such sealing position as will be explained later.

,When it is desired to lock the valve 30 open and render the device inoperative,.a suitable shifting tool such as that illustrated and described in the aforementioned U.S. Pat. No. 3,05l,243 to Grimmer is utilized to engage the recesses 85 in the shiftable lock sleeve 40 and to move it downwardly, moving the valve operator 32 downwardly therewith in order to swing the valve 30 to its open position, shown in FIGS. l-A, l-B, l-C and 1-D. With the shiftable lock sleeve moved to its lower position and locked in such position by the engagement of its exterior buttress-like flanges with the buttress-like flanges in the snap ring, the valve cannot move from its open position toward its closed position. Accordingly, production of the well can be continued as desired.

When the lock sleeve 40 is moved downwardly from its upper position shown in FIG. l-A and the upper end thereof clears the plug 102 which is disposed in the aperture 100, the control fluid pressure, conducted to the valve 20 from the surface controller 29 through the control fluid conduit 28 and through the longitudinal eccentric passage 26 in the upper housing to the annular chamber 75, will act on the plug 102 and tend to move it inwardly to displace it from its sealing position in the aperture 100. This displacement cannot at this time take place because the washer 106 will then engage the bottom 10la of the counterbore 100 and the outer ends of the shear pin 107 will engage the washer 106 to prevent further inward movement of the plug 102. Thus, it may be readily seen that the plug will remain intact since the shear value of the shear pin exceeds the forces developed by normal control fluid pressure acting across the plug. If, however, it is desired to install a supplementary safety valve within the valve device 20 and to control such supplementary valve by control fluid pressure conducted thereto from the surface controller 29, it is only necessary to increase the control fluid pressure to a value substantially above normal until such increased pressure is sufficient to shear the shear pin 107 and permit the plug 102 to -move inwardly out of aperture 100 as shown in FIG. 8,

and into the central bore of the device 20 where it will fall harmlessly to the bottom of the wall.

In the absence of the plug 102, the aperture 100 will be open and control fluid pressure can pass freely from the chamber into the interior of the sleeve housing 70.

A supplementary safety valve such as the valve 120 is then attached to the lower end of a suitable locking device such as the locking device 121 and lowered into the wall on a suitable running tool and string of wireline tools (not shown) and installed as shown in FIGS. 9-A and 9-B. The locking device 121 has keys 122 having bosses 123 which engage in the lock recesses 61 of the landing nipple 23 and support the valve 120 therein in the proper position. Suitable seal rings 124 carried by the locking device 121 seal between the device and the inner wall 42 of the landing'nip'ple while suitable seals v 125 carried on the valve 120 near the lower end thereof engage the inner wall 43 of the lower sub 45 at the lower end of the safety valve device 20 to seal between the lower end of the supplementary safety valve 120 and the lower portion of the safety valve device 20. Thus, control fluid passing through the open aperture in the sleeve housing 70 is confined to the region between the supplementary valve and the inner wall of the device 20 between the upper and lower seal assemblies 124 and 125. This control fluid is then conducted through the inlet port 128 into the mechanism of the supplementary valve for actuation of the same. Thus, the flow of well fluids through the well tubing T is controlled by controlling the supplementary valve from the surface in exactly the same manner as was the valve device 20.

When suitable pilot means (not shown) in the surface controller 29 responds to a particular condition and acts to bleed or relieve'the control pressure from the control fluid conduit 28, the supplementary valve 120.

will close to stop flow through the valve. When such particular condition has been cleared up and the surface controller 29 used to reinstate control pressure to the system, the valve 120 will open so that production from the well may be continued in the usual manner.

Thus, it has been shown that a subsurface safety valve has been provided which is controllable from the surface and which can be locked in open position by sliding a shiftable lock sleeve downwardly which will force the operator downwardly and, therefore, force the valve closure member to its open position; that the lock sleeve can be locked in its lowermost or any intermediate position sothat upward movement of the lock sleeve from suchposition is not possible; that such valve can be locked in open position and production continued from the well if desired; that a supplemenhigher than normal level to open up a passage or port means in the valve mechanism and establish means for admitting control fluid into the inner bore of the device where the supplementary safety valve is disposed. Of course, it si understood that a packoff mechanism or other tool can be installed in place of the supplementary safety valve to packoff a faulty valve such as the safety valve device 20, in which case the locking mandrel 121 would carry an open bore valveless tubular body between the upper and lower seal assemblies 124 and 125 to that production fluids would be conducted therethrough past the faulty valve. If such packoff tool is used, it is not necessary to conduct control fluid thereto; so the plug 102 is left intact in its place closing the lateral aperture 100. A packoff tool is usable, for instance, in cases where the control fluid conduit 28 breaks, and also at the same time, a failure occurs in the plug 102 or in the seals 124 or 125 of the safety valve such that well fluids otherwise escape from the well tubing through the faulty safety valve and through the broken control fluid conduit 28 into the surrounding casing which may not be able to withstand high well pressures. A packoff tool thus prevents such leakage and permits continued production from the well but without protection previously afforded by the surface controlled downhole safety valve 20.

A modified form of the invention is illustrated in FIGS. and 11 where it is indicated generally by the numeral 150.

In this form of the invention, the upper housing section 55, having the offset or eccentric control fluid passage 26, has mounted therein a modified sleeve housing 151. This sleeve housing has at least one lateral aperture or control fluid passage 152 formed in its wall and this aperture is enlarged as at 153 providing a seating surface 154 and is internally threaded as at 155 to receive a plug 156 having its inner end portion 157 reduced in diameter to fit within the aperture 152 and to provide a sea] surface 158 which engages the seating surface 154 of the aperture to prevent leakage of control fluid around the plug.

The plug 156 is provided with a bore 160 therethrough and this bore is enlarged as at 161 to provide a stop shoulder 162. A sealing or rupture disk 164 is disposed in the enlarged bore 161 of the plug and engaged against the stop shoulder 162 where it is sealingly secured in place by silver solder, epoxy cement, or the like, to seal the plug bore 160 against leakage of control fluid therethrough. If desired, the disk may be dished or cupped and its convex surface faced inwardly as is clearly shown in FIG. 10.

It will be noted that the inner side 164a of the sealing or rupture disk is substantially in engagement with the exterior wall surface of the shiftable sleeve 40 which helps to support the disk against premature rupture or displacement from its sealing position, although the disk is preferably sufficiently strong to make such support normally unnecessary.

If, after the shiftable lock sleeve 40 has been shifted to its lower position to force the valve 30 open and to hold it in this open position, it is desired to install a supplementary device, such as the supplementary safety valve 120, in the device 150, the control fluid pressure is increased until the disk 164 is displace or ruptured to open the bore 160 through the plug 156 as shown in FIG. 11, thus providing a lateral control fluid passage through the wall of the sleeve housing 151. Subsequently, the supplementary safety valve is installed and actuated from the surface as before explained.

Thus, it will be seen that the plug 156 of the device 150 serves exactly the same function as does the plug 102 of the device 20 previously described and that the lateral aperture of the device 20 and the aperture 152 of the device each are opened in exactly the same manner, that is, by increasing the control fluid pressure until the plug fails, opening the lateral control fluid passage.

Another modified form of the invention is illustrated in FIGS. 12 and 13 where it is indicated generally by the numeral 200. The device 200 may be exactly like the devices previously described below its connector 52 in whose bore the piston 32a is slidable. Above the connectors 52 there are substantial differences in structure. For this reason, only the upper portion of the device 200 is shown.

The upper housing 201 is substantially the same as the upper housing 55 of the device 20 first described but is considerably longer. The upper housing 201 is threadedly attached at its lower end to the upper threaded end of the connector 52 and its upper end is internallythreaded as at 204 for attachment to the landing nipple 23. An eccentric of offset longitudinal control passage 206 is provided in the upper portion of the upper housing 201 and is threaded as at 207 at its upper end for'attachment of the control fluid conduit 28. The passage 206 has its lower end opening into the enlarged bore 210 of the upper housing. Thus, control fluid is conducted from a surface controller such as the surface controller 29 on the surface through the con trol fluid conduit 28 to the device 200 where it enters through the passage 206 and from there is conducted to the valve mechanism as will be described.

A sleeve housing 215 is disposed within the upper housing 201 and its reduced upper end portion 216 is telescoped into the intermediate bore 217 in the upper portion of the upper housing 201 as shown. A seal ring such as the o-ring 218 is disposed in a suitable external annular recess nearthe upper end of the sleeve housing 215 and seals between the upper end of the sleeve housing and the upper housing. The outside diameter of the sleeve housing 215 is somewhat less than the inside diameter of the upper housing so that an annular space or passage 220 is provided between the sleeve housing and the upper housing. Itis readily seen that the o-ring 218 seals the upper end of this annular passage 220. Thelower end portion 222 of the sleeve housing is reduced in diameter and is telescoped into the enlarged portion 224 of the bore 226 of the spacer sleeve 228 while a seal ring such as the o-ring 229 seals between the sleeve housing and the spacer sleeve as shown. The lower end of the spacer sleeve 228 is supported upon the upper end of the connector 52 and is provided with a groove or slot 230 across its lower end to provide a radial passage through which control fluid may be conducted from the annular passage 220 into the piston chamber 2 where it acts downwardly upon the piston 32a to move the valve operator 32 down for opening the valve.

As in the preceeding embodiment, the spacer sleeve is telescoped over the upper end of the valve operator 32 and a seal ring such as the o-ring 232 disposed in a suitable internal annular recess formed in the spacer sleeve seals between the spacer sleeve and the exterior of the valve operator to close the upper end of the piston chamber 33.

Thus, control fluid is conducted from the offset or eccentric passage 206 into the upper end of the annular passage 220 and from the annular passage 220 through the cross slot or groove 230 of the spacer sleeve into the chamber 33 to operate the piston.

An elongate slidable lock sleeve 240 has its upper portion disposed in the sleeve housing 215 and its lower portion extending down into the spacer sleeve 228 as shown. The upper portion of the lock sleeve is provided with external buttress-like flanges or threads 241 which may be exactly like the external flanges 86 on the lock sleeve 40 of the device 20. The lock sleeve 240 is also provided with a plurality of suitable internal annular recesses 85 which are engageable by a suitable shifting tool such as the shifting tool ST previously mentioned for shifting the sleeve to a lower position for holding the valve open or in an inoperative position as was before explained.

A seal ring such as the o-ring 242 is disposed in a suitable external annular recess near the upper end of the shiftable lock sleeve to seal between the lock sleeve and the sleeve housing. A seal ring such as the o-ring 243 is disposed in a suitable internal annular recess formed in the mid portion of the spacer sleeve 228 to seal between the spacer sleeve and the lower end of the slidable lock sleeve 240. A seal ring such as the o-ring 244 is disposed in a suitable external annular recess formed in the mid portion of the lock sleeve. When the sleeve is in its upper position as shown in FIG. 12, the seal ring 244 does not seal between the slidable lock sleeve and the spacer sleeve because the seal ring 244 is disposed in a slightly enlarged intermediate bore 246 in the spacer sleeve between the main bore 226 and the enlarged bore 244 where it is ineffective to provide a seal.

The enlarged bore 224 at the upper end of the spacer sleeve is considerably longer than the length of the reduced portion 222 of the sleeve housing, telescoped thereinto thus providing a wide internal annular recess 250 between the lower end of the enlarged bore 224 and the lower end of the sleeve housing 215.

A retainer ring 251 having one or more apertures 252 through the wall thereof is disposed in the lower part of the recess 250 and carries one or more shear pins 253 disposed in such apertures, each shear pin having its inner end disposed in a suitable external annular groove formed in the mid portion of the shiftable lock sleeve 240 to retain the shiftable sleeve in its upper inoperative position shown in FIG. 12. Between the retainer ring 251 and the lower end of the sleeve housing 251, a snap ring or annular pawl 90 is disposed in the internal annular recess 250 and this snap ring may be exactly the same as the snap ring 90 in the device previously described and which is shown in FIG. l-A. The snap ring is provided as before explained with internal buttress-like projections and the exterior of the upper portion of the shiftable lock sleeve 240 is formed with complementary exterior buttress-like projections which may be exactly like those on the sleeve 40 in the device 20 previously described.

The shiftable sleeve 240 is shifted to its lower position through use of a suitable shifting tool such as the shifting tool ST which engages the internal recesses 85 in the shiftable sleeve and when a downward force of sufficient magnitude is applied to the sleeve, the pins 253 are sheared and the sleeve moved downwardly, the lower end of the sleeve contacting the upper end of the operator 32, if the operator is in an upper position, and forcing the operator 32 downwardly to a lower position wherein it holds the valve (not shown) open. During downward movement of the lock sleeve 240, the external buttress-like flanges thereon cam their way through the snap ring which is inherently sprung inwardly and when the sleeve reaches a lower position any tendency for it to move upwardly thereafter will result in engagement of the abrupt surfaces on the complementary buttress-like flanges of the sleeve and snap ring, thus preventing further upward relative movement of the sleeve. Thus, the shiftable sleeve is locked in a lower position holding the valve open.

It will be noted that the sleeve housing 215 is provided with a lateral port or passage 270 near its upper end and that this port is closed with a plug 271 which may be exactly like the plug 102 in the device 20, or like the plug 156 in the device as shown. The plug 271 prevents the passage of control fluid from the annular passage 220 exterior of the sleeve housing to the interior thereof.

It will further be noticed that the spacer sleeve 228 is provided with a lateral aperture 276 located immediatelyabove the seal ring 243 in the mid portion of this spacer sleeve. When the shiftable lock sleeve 240 is immediately above its upper inoperative position, as is shown in FIG. 12, control fluid conducted to the device 200 through the control fluid conduit 28 passes through the eccentric or offset passage 206 into the annular passage 220 between the upper housing 201 and the sleeve housing 215 and from the annular passage through the cross slots 230 at the lower end of the spacer sleeve into the piston chamber 33 for operation of the piston and actuation of the valve.

Control pressure can also pass from the annular passage 220 through the lateral aperture 276 in the spacer sleeve but cannot move downwardly past the seal ring 243. It can, however, move upwardly between the exterior of the lock sleeve 240 and interior of the spacer sleeve 228 and past the seal ring 244 which is spaced from the inner wall of the immediate bore 246 and can pass beyond the retaining ring 251 and the snap ring 90 and upwardly between the shiftable lock sleeve 240 and the interior of the sleeve housing 215 as far as the seal ring 242. The control pressure thus acts on the inward side of the plug 271 and at the same time acts on the outward side of the plug since the outward side is clearly exposed to fluid in the annular passage 220. It will thus be seen that when the lock sleeve 240 is in its upper position, as shown in FIG. 12, the plug is isolated from well fluids and no differential pressure can act on it to shear or displace the same since its ends are exposed to a common pressure, namely, control fluid pressure. 7

When the shiftable sleeve 240 is moved to its lowermost position as is shown in FIG. 13, the seal ring 244 carried by the lock sleeve comes to rest in sealing position above the lateral aperture 276 in the spacer sleeve, thus preventing control fluid pressure from moving upwardly therepast. At the same time, when the sleeve the plug 271. The plug now has its inner end exposed to well pressure while its outer end is still exposed to control fluid pressure.

When the shiftable sleeve 240 is in its lower position as shown in FIG. 13, the device 200 is understandably held inoperative, the shiftable sleeve being locked by the snap ring in its lower position holding the valve operator 32 down and thus holding the valve open.

If it is desired to install a supplementary safety valve, such as the supplementary safety valve 120 in the device 200 and to control it from the surface, it will be necessary to raise the control fluid pressure to a level which will cause the plug 271 to fail, thus opening the lateral passage 270 through the wall of the sleeve housing and admit cntrol fluid pressure into the interior of the device 200 in the manner already described.

The advantages of the structure just described and which is shown in the FIGS. 12 and 13 are that, under normal conditions when the shiftable sleeve 240 in its upper position and the plug 271 is intact, the plug has clean noncorrosive control fluid on both of its sides and is isolated from well fluids which may be corrosive and ladened with abrasive particles, etc., and the plug will not be subjected to pressure differentials.

A further modified form of the invention is illustrated in FIGS. 14 and 15 and is there indicated by the number 300. This form of the invention is very similar to the form last described and its lower portion from the connector 52 of the housing downwardly is exactly the same as the embodiments previously described. Attached to the upper end of the connector 52 is an upper housing 301 which may be exactly like the upper housing 201 of the previous embodiment and this upper housing 301 is threadedly attached to the lower end of the landing nipple 23 thereabove and has an offset or eccentric longitudinally disposed control fluid passage 303 connected at its upper end to the control fluid line 28 and its lower end opening into the enlarged bore 310 of the upper housing as in the previous embodiments. Disposed within the upper housing is a sleeve housing 312 which is similar to the sleeve housing 215 in the embodiment previously deacribed but is not provided with an aperture in the wall thereof. The upper reduced portion 314 of the sleeve housing is telescoped into the intermediate bore 315 of the upper housing and a seal ring such as the o-ring 316 seals between the upper end of the sleeve housing and the upper housing. The outside diameter of the sleeve housing 312 is somewhat less than the inside diameter of the upper housing, thus providing an annular passage 320 therebetween. The lower reduced diameter position 321 of the sleeve housing is telescoped into the enlarged bore 322 at the upper end of the spacer sleeve 324 and a seal ring such as the o-ring 325 seals between the sleeve housing and the spacer sleeve.

The length of the reduced diameter portion 321 on the lower end of the sleeve housing 312 is somewhat shorter than the length of the enlarged bore 322 in which it is received, thus providing a wide internal annular recess 350.

A retainer ring 352 having one or more radial apertures in its wall is disposed in the annular recess 350 and one or more shear pins 354 have their outer ends disposed in the one or more apertures in the retainer ring 352 while their inner ends are engaged in a suitable external annular recess formed in an elongate shiftable lock sleeve 340 having its upper portion disposed in the sleeve housing 312 and its lower portion extending down into the spacer sleeve 324 as shown in FIGS. 14 and 15. The pins 354 obviously retain the lock sleeve in its upper inoperative position shown in FIG. 14.

An elongate shiftable or slidable lock sleeve 340 is provided with a plurality of internal recesses which are engageable by a suitable shifting tool such as the shifting tool ST previously mentioned for shifting the sleeve from the upper portion shown in FIG. 14 to its lower position shown in FIG. 15. The slidable lock sleeve 340, like the lock sleeves 40 and 240 of the devices 20 and 200, previously described, has external buttress-like flanges or threads 364 formed about its upper portion, each such flange or thread having a .lower side which slopes downwardly and inwardly to provide a cam surface indicated by the numeral 364a.

A ratchet pawl in the form of a snap ring 90, which may be identical with the snap rings previously described is disposed in the recess 350 above the retainer ring and has ratchet teeth of flanges 365 formed therein, each such flange having its upper side sloping downwardly and inwardly to provide a cam surface indicated by the numeral 365a which cooperates with the cam surfaces 364a on the flanges of the lock sleeve 340 as will be explained.

The lock sleeve 340 is shifted to a lower position to hold the valve open by lowering a suitable shifting tool into the well flow conductor, engaging it in the recesses 85 in the lock sleeve 340 and applying a downward force thereto. This downward force shears the pins 354 in the retainer ring 352 and moves the lock sleeve downwardly through the snap ring 90. During downwardmovement of the lock sleeve, the cam surfaces 364a on the lower sides of its external buttress-like flanges coact with similar cam surfaces 365a on the upper sides of complementary flanges in the snap ring to force open the snap ring and permit the lock sleeve to move downwardly therethrough. When the slidable lock sleeve 340 reaches its lower position as is shown in FIG. 15, or an intermediate position, it is locked in such position by the pawl snap ring 90 and holds the valve operator member 32 in such lower position and thus holds the valve (not shown) in open position as was previously described.

Control fluid is conducted to the device 300 for holding the valve therein open, such control fluid passing through the control fluid conduit 28 connected to the upper housing and through the eccentric passage 303 into the enlarged bore 310 of the upper housing section and being conducted through the annular passage 320 between the upper housing 301 and the sleeve housing 312 and spacer sleeve 324 until it passes through the cross slot 330 formed in the lower end of the spacer sleeve and into the piston chamber 33 where it acts downwardly on the piston 32a for actuating the valve (not shown) therebelow.

The spacer sleeve 324 is provided with a lateral passage or aperture 332 formed in the wall thereof and a pair of seal rings such as the seal rings 334 and 335 disposed in suitable internal annular recesses formed in the inner wall of the spacer sleeve 324 seal between the spacer sleeve 324 and the exterior of the lower portion of the shiftable sleeve 340 above and below the lateral aperture 332, respectively, so that control fluid passing from the annular passage 320 through the lateral aperture 332 is confined between the two seal rings 334 and cannot move therepast.

The lock sleeve 340 is provided with a lateral aperture 375 through its wall located just below the shear pin groove formed in the exterior thereof and this aperture may be closed by any suitable means such as one of the plugs previously described or may be sealed by a suitable disk such as the disk 377 secured therein much like the disk 164 is secured in place in plug 156 of the device of FIGS. 10 and 11. It will be noted that the disk 377, when the shiftable sleeve 340 is in its upper position shown in FIG. 14, is in a well fluid environment since the inner side of the disk is exposed to well fluids existing in the bore of the lock sleeve 340 and its outward face is exposed to well fluids conducted thereto from the bore of the shiftable sleeve 340 since such well fluids can pass around the upper end of the lock sleeve and downwardly between it and the sleeve housing, past the snap ring and the retainer ring, and between the shiftable sleeve 340 and the spacer sleeve 324 as far as the upper seal ring 334 located just above the lateral port 332 in the spacer sleeve. Thus, during normal operation of the well, the disk 377 or other suitable plug which may be used in place thereof is not subjected to differential pressures and therefore there is no tendency for the same to be displaced or ruptured prematurely. The plug or disk is obviously isolated from control fluid pressure.

When the shiftable sleeve 340 is moved to its lower position wherein it is locked in such position by the snap ring 90 and wherein it holds the valve operator 32 in its lower position to lock the valve therebelow open, the aperture 375 in the wall of the lock sleeve willthen be located between the two o-rings 334 and 335 in the wall of the spacer sleeve and, therefore, will be in direct communication with the aperture 332 in the wall of the spacer sleeve. Control fluid pressure may then be conducted through the aperture 332 in the spacer sleeve into the sleeve between the spacer sleeve and the exterior of the lock sleeve and into the aperture 375 where it will act against the outer face of the disk 377 or against the outer end of such other suitable plug as may be used in lieu of the disk 377. The disk or plug, whichever is used, should preferably be sufficiently strong to withstand normal control fluid pressures. If, however, a supplementary subsurface safety valve such as the supplementary safety valve 120 is to be installed in the device 300 and is to be controlled from the surface, then prior to the installation of such supplementary safety valve the control pressure must be increased until such control pressure acting on the disk 377 will cause the disk to be ruptured or be displaced from its place in the aperture 375 of the shiftable sleeve 340, thus opening the aperture or lateral passage 375 so that control fluid pressure will be conducted to the interior of the lock sleeve 340 where it can act on the supplementary safety valve 120 to actuate the same.

From the foregoing it will be seen that a subsurface safety valve for well flow conductors has been provided which is operated by control fluid pressure conducted thereto from a surface controller located on the surface of the earth; that the safety valve has means therein for locking the valve mechanism in an open or inoperative position or in an intermediate position between closed and open positions; that the safety valve also has means therein responsive to control fluid pressure for opening a fluid passage into the interior of the safety valve by increasing the control pressure substantially above normal after the locking means has first been moved to position locking the valve mechanism in an open or partly open position; and that a supplementary safety valve may then be installed in the original valve and actuated by control fluid pressure from the surface conducted thereto through the newly opened passage. Further, it has been shown that such pressure responsive means for opening the control fluid passage into the interior of the safety valve may be a plug, a disk, or a disk in a plug, or the like; that the plug or disk can be carried in the housing or in a slidable sleeve; that such plug or disk may normally be disposed in an environment of well fluids, or of control fluid, or disposed so that one of its ends is exposed to well fluids and the other of its ends is exposed to control fluid; and that, in either case, the plug or disk can be displaced or opened only after the slidable sleeve has been moved or shifted from its inoperative position to a position engaging the valve mechanism to hold the valve open or partly open.

Thus, the subsurface safety valve of this invention fulfills all of the objects set forth in the beginning.

The foregoing description of the invention is explanatory only, and changes in the details of construction illustrated may be made by those skilled in the art, within the scope of the appended claims, without departing from the true spirit of the invention.

What is claimed and desired to be secured by letters patent is:

1. A well flow conductor valve including: a housing having means for connecting it in flow communication with a well flow conductor; valve means disposed in the housing and movable therein between open and closed positions for controlling flow through the housing; operating means in said housing movable longitudinally thereof for actuating said valve to move the same between the open and closed positions; locking means in the housing initially in an inoperative position spaced from said operating means and movable to a position engaging said valve operating means to positively lock said valve operating means in position holding said valve in open position; fluid pressure responsive means on said operating means; means for conducting control fluid pressure to said valve housing for acting on said fluid pressure responsive means to control movement of said operating means in response to such control fluid pressure; means at the surface for controlling fluid pressure conducted through said control fluid conductor means to the valve in response to predetermined conditions; and means providing a control fluid passage into the interior of the valve housing responsive to an increased control fluid pressure after said locking means has been moved to position locking said valve means in open position, said increased control fluid pressure being substantially higher than the control fluid pressure required to operate said operating means.

2. The device of claim 1 in combination with a supplementary safety valve disposed therein and actuated by control fluid pressure conducted to the same through said control fluid passage.

3. The device of claim 1 wherein said means for providing said control fluid passage into the interior of said valve includes: a port in the wall of said housing; plug means plugging said port; and means releasably retaining said plug means against displacement from said port means and releasable in response to said increased control fluid pressure.

4. The device of claim wherein said plug in said port has its inner and outer sides subjected to control fluid pressure when said sleeve is in said inoperative position.

5. The device of claim 3 wherein said plug in said port has its inner and outer ends subjected to well fluid pressure when said sleeve is in said inoperative position.

6. The device of claim 3 wherein said plug means includes a plug disposed in said port and seal means engaged between said plug and the wall of said port for preventing flow of control fluid through said port when said plug is disposed therein, and said releasable means is a shear pin disposed in an aperture in said plug and having at least one of its ends engaged with said housing, said shear pin being shearable responsive to said increased control fluid pressure to displace said plug from said port, whereby said control fluid passage into the interior of said valve housing is opened upon a substantial increase in control fluid pressure.

7. The device of claim 3 wherein said plug means is a disk sealingly disposed in said port and being displaceable from such sealing position by said increased control fluid pressure.

8. A well flow conductor valve comprising: a housing having means connecting it in flow communication with a well flow conductor; valve means disposed in the housing and movable therein between open and closed positions for controlling flow through the housing; operating means in said housing movable longitudinally thereof for actuating said valve to move the same between open and closed positions; fluid pressure responsive means on said operating means; means for conducting controlfluid pressure to said valve housing for acting on said fluid pressure responsive means to control movement of said operating means in response to such control fluid pressure; means at the surface for controlling fluid pressure conducted through said control fluid conductor means to the valve in response to predetermined conditions; and means providing a control fluid passage into the interior of the valve housing responsive to an increased control fluid pressure substantially higher than the control fluid pressure required to operate said operating means.

9. The device of claim 8 wherein said means for providing said control fluid passage into the interior of said valve is a port in the wall of said housing and includes plug means plugging said port and means releasably retaining said plug means against displacement from said port means and releasable in response to said increased control fluid pressure.

10. The device of claim 9 wherein said plug is a disk sealingly disposed in said port and being displaceable from such sealing position by said increased control fluid pressure.

11. The device of claim 9 in combination with a supplementary safety valve disposed therein and actuated by control fluid pressure conducted to the same through said control fluid passage. 7

12. The device of claim 9 wherein said plug in said port has its inner and outer sides subjected to control fluid pressure when said sleeve is in said inoperative position.

l3. The device of claim 12 in combination with a supplementary safety valve disposed therein and actuated by control fluid pressure conducted to the same through said control fluid passage.

14. The device of claim 9 wherein said plug in said port has its inner and outer ends subjected to well fluid pressure when said sleeve is in said inoperative position.

15. The device of claim 14 in combination with a supplementary safety valve disposed therein and actuated by control fluid pressure conducted to the same through said control fluid passage.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 a 88 2 a 935 Dated y 13 a 1975 Inventor(s) Michael B, Calhoun It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 3, line 13: After "bias" insert --of--.

Column H, line 11: After "supplementary" insert --valve-.

Column 7, lines 8 and 9: for "sperture" read --aperture.

Column 8, line 9: for "wall" read -well.

Same column, line 17: for "wall" read -well.

Column 9, line 5: for "si" read is-.

Column 10, line 26: for "of" read --or-.

Column 12, lines 25 and 26: for "immediatelyabove" read immediately above-.

Column 13, line 15: for "cntrol" read -control.

Same column, line 51: for "position" read -portion-.

Column 17, line 1: for "The device of claim 5" read -The device of claim 3.

Signed and Scaled this A ttest:

RUTH C. MASON Arresting Officer C. MARSHALL DANN (ummissinner oj'PalenIs and Trademarks 

1. A well flow conductor valve including: a housing having means for connecting it in flow communication with a well flow conductor; valve means disposed in the housing and movable therein between open and closed positions for controlling flow through the housing; operating means in said housing movable longitudinally thereof for actuating said valve to move the same between the open and closed positions; locking means in the housing initially in an inoperative position spaced from said operating means and movable to a position engaging said valve operating means to positively lock said valve operating means in position holding said valve in open position; fluid pressure responsive means on said operating means; means for conducting control fluid pRessure to said valve housing for acting on said fluid pressure responsive means to control movement of said operating means in response to such control fluid pressure; means at the surface for controlling fluid pressure conducted through said control fluid conductor means to the valve in response to predetermined conditions; and means providing a control fluid passage into the interior of the valve housing responsive to an increased control fluid pressure after said locking means has been moved to position locking said valve means in open position, said increased control fluid pressure being substantially higher than the control fluid pressure required to operate said operating means.
 2. The device of claim 1 in combination with a supplementary safety valve disposed therein and actuated by control fluid pressure conducted to the same through said control fluid passage.
 3. The device of claim 1 wherein said means for providing said control fluid passage into the interior of said valve includes: a port in the wall of said housing; plug means plugging said port; and means releasably retaining said plug means against displacement from said port means and releasable in response to said increased control fluid pressure.
 4. The device of claim 5 wherein said plug in said port has its inner and outer sides subjected to control fluid pressure when said sleeve is in said inoperative position.
 5. The device of claim 3 wherein said plug in said port has its inner and outer ends subjected to well fluid pressure when said sleeve is in said inoperative position.
 6. The device of claim 3 wherein said plug means includes a plug disposed in said port and seal means engaged between said plug and the wall of said port for preventing flow of control fluid through said port when said plug is disposed therein, and said releasable means is a shear pin disposed in an aperture in said plug and having at least one of its ends engaged with said housing, said shear pin being shearable responsive to said increased control fluid pressure to displace said plug from said port, whereby said control fluid passage into the interior of said valve housing is opened upon a substantial increase in control fluid pressure.
 7. The device of claim 3 wherein said plug means is a disk sealingly disposed in said port and being displaceable from such sealing position by said increased control fluid pressure.
 8. A well flow conductor valve comprising: a housing having means connecting it in flow communication with a well flow conductor; valve means disposed in the housing and movable therein between open and closed positions for controlling flow through the housing; operating means in said housing movable longitudinally thereof for actuating said valve to move the same between open and closed positions; fluid pressure responsive means on said operating means; means for conducting control fluid pressure to said valve housing for acting on said fluid pressure responsive means to control movement of said operating means in response to such control fluid pressure; means at the surface for controlling fluid pressure conducted through said control fluid conductor means to the valve in response to predetermined conditions; and means providing a control fluid passage into the interior of the valve housing responsive to an increased control fluid pressure substantially higher than the control fluid pressure required to operate said operating means.
 9. The device of claim 8 wherein said means for providing said control fluid passage into the interior of said valve is a port in the wall of said housing and includes plug means plugging said port and means releasably retaining said plug means against displacement from said port means and releasable in response to said increased control fluid pressure.
 10. The device of claim 9 wherein said plug is a disk sealingly disposed in said port and being displaceable from such sealing position by said increased control fluid pressure.
 11. The device of claiM 9 in combination with a supplementary safety valve disposed therein and actuated by control fluid pressure conducted to the same through said control fluid passage.
 12. The device of claim 9 wherein said plug in said port has its inner and outer sides subjected to control fluid pressure when said sleeve is in said inoperative position.
 13. The device of claim 12 in combination with a supplementary safety valve disposed therein and actuated by control fluid pressure conducted to the same through said control fluid passage.
 14. The device of claim 9 wherein said plug in said port has its inner and outer ends subjected to well fluid pressure when said sleeve is in said inoperative position.
 15. The device of claim 14 in combination with a supplementary safety valve disposed therein and actuated by control fluid pressure conducted to the same through said control fluid passage. 